ngraham recommended that I split up https://phabricator.kde.org/D27438 into three patches:
1. This patch - the foundation code to get landed first so that the other two patches can be done as patches that change two separate lines instead of just one
2. Tablet Mode increases tray icon spacing
3. Increase tray icon spacing slightly on Non-Tablet Mode (half of the amount it increases by in Tablet Mode)
This patch is the start of that process, made to be landed first so that patches 2 and 3 can then follow while only having a diff that affects one different line each of this patch's changed lines.